1. Field of the Invention
In particular, the invention concerns a roll stabilisation system for a moving submarine vehicle.
2. Description of the Relation Art
It is known that autonomous, remotely controlled or towed vehicles are used in submarine applications.
In the case of a static or slow-moving vehicle, the respective positions of the centre of gravity, the centre of volume (the point of application of the buoyancy) and any axis of rotation (in the case of a towed vehicle for example) are often such that the vehicle positions itself naturally in the zero roll position when it is submerged, with the return torque thus created toward the vertical position generally being sufficient to ensure the stability of the vehicle.
On the other hand, in the case of a vehicle that has a preferential direction of motion, hereinafter known as the “vehicle axis”, and which is moving quite rapidly (from a few knots to over 10 knots) along this axis, the hydrodynamic effects on the vehicle can overcome the static stabilisation forces described above, and thus cause the vehicle to become unstable.
Stabilisation solutions do exist, which consist, for example, of equipping the vehicle with a list sensor, and of controlling the guidance/orientation means (actuators, control surfaces, fins, etc.) so as to actively control this roll.
These systems have the following drawbacks however:                The need to equip the vehicle with a power source (internal or external),        The need to equip the vehicle with a list sensor,        The need to fit motor-driven actuators on the vehicle,        The need to create a control loop,        The power consumed by the actuators, which are often electrical.        